I understand raid 10 and raid 5, and I know quite a bit about their strength's and weaknesses in normal applications. What I need assistance with is a special application of these drives.
The situation is this: We will have (14) 1TB Near Line SAS drives (7200 RPM drives with SAS connections for better throughput) http://www.seagate.com/docs/pdf/datasheet/disc/ds_barracuda_es_2.pdf
It will be for our backup server. So heavy writes of tiny delta files (1k or so) up to files in the hundred meg range. It gets hit by several hundred servers around the same time at night 9pm or so all through the night. The only time anything is read from it is when we need to recover a file, or when we start replicating the data to an offsite storage unit.
We have had issues before with the replication causing high read queues and never actually completing on our current setup (7 drives with sata throughput) which is why we are considering raid 10.
In such a large write heavy situation is raid 10 reccomended ? Or will the fact that we have 14 drives to spread the writes across make up for the difference if we go with Raid 5? Is there even a performance boost to reads with raid 10 vs 5 ?